v0.12.0: fix rpath format
* set CMAKE_INSTALL_RPATH w/ list syntax of string syntax * add Context::updateGL() to allow use to call `glewInit()` from within windows DLL (requirement) for multi-context scenarios and bump minor sdk version * add `add_library(drishti::drishti ALIAS drishti)` in install section for `add_subdirectory()` compatibility * update driahti-face-test sample config file defaults ``` set(CMAKE_INSTALL_RPATH "${DRISHTI_ORIGIN}/../lib" "${DRISHTI_ORIGIN}") ```